The official Podio iOS SDK by Podio calls the RESTful Podio API which allows developers integration with event-driven applications and to utilize webhooks. It supports iOS 7.0+ and Mac OS X 10.9+.
Last year, Facebook announced that it would launch a set of business-centric tools around WhatsApp. The company has also long stated that it would eventually monetize its various messaging platforms. Facebook has taken a step towards both goals with the introduction of the WhatsApp Business API.
Microsoft has announced general availability of Office 365 APIs, including Mail, Calendar, Contacts, and Files, as well as availability of Office 365 iOS and Android SDKs.
Really Simple Systems, a cloud-based CRM provider, has announced the release of version 4 of their API. The update comes at the request of the developer community and adds new features, while increasing security. Improvements include the ability to control authentication at the user level.